Absorbent material and system and method for manufacturing the same

Abstract

The fiber-SAP particles include a superabsorbent core particle (SAP core particle) and a plurality of fibers attached to and extending from the SAP core particle. The fiber-SAP particles can be formed in a fluidized bed chamber using a spray drying process. The fiber-SAP particles can be incorporated into absorbent cores and articles, such as disposable diapers.

Description

[0001] This application is a divisional application with application number 201880027815.5, application date February 26, 2018, and invention name “Absorbent material and its manufacturing system and method”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 463,714 (pending), filed February 26, 2017; and claims the benefit of U.S. Provisional Patent Application No. 62 / 482,277 (pending), filed April 6, 2017. The entire contents of each of U.S. Provisional Patent Application Nos. 62 / 463,714 and 62 / 482,277 are incorporated herein by reference and made a part of this disclosure for all purposes. Technical Field

[0004] The present disclosure generally relates to absorbent materials, absorbent particles, core composites, and disposable absorbent articles containing the same. The present disclosure also relates to systems and devices and methods suitable for making the same. At least some aspects of the present disclosure are particularly suitable for or related to disposable absorbent articles, such as baby diapers, infant and toddler training pants, and adult incontinence diapers and pants. Background Art

[0005] Absorbent articles, such as diapers, typically include three basic structural elements, including: (1) a top sheet forming an inner surface; (2) a back sheet forming an outer surface; and (3) an absorbent core placed between the top sheet and the back sheet. The absorbent core is typically designed to accommodate and distribute fluid passing through the top sheet. A typical absorbent core is made of a high or super absorbent polymer (SAP), which is stabilized by an absorbent matrix. SAP is typically made of materials such as polyvinyl alcohol, polyacrylates, various grafted starches, and cross-linked sodium polyacrylate. SAP can be in the form of particles, fibers, foams, nets, balls, regular or irregularly shaped agglomerates, and films. The absorbent matrix is ​​typically defiberized wood pulp or similar materials. The absorbent matrix is ​​very bulky relative to the top sheet, back sheet, and SAP.

[0006] It may be desirable to improve certain aspects of absorbent cores, such as certain fluid handling capabilities, including liquid absorption rate and other absorption properties, liquid distribution properties, and SAP fixation within the absorbent core. It may also be desirable to provide systems and methods where the formation of SAP and related fiber networks is integrated into systems and methods for manufacturing absorbent articles, cores, and materials.

[0007] U.S. Patent No. 7,381,294 (Suzuki '294) and No. 6,794,557 (Klemp '557) provide background information on the design and manufacture of microfibrillated fibers related to the present disclosure, as well as disposable absorbent articles and products incorporating absorbent core composites and structures. Therefore, the disclosures of Suzuki '294 and Klemp '557 are incorporated herein by reference and constitute a part of the present disclosure, but only to the extent that the incorporated subject matter provides background information and / or exemplary composites and processes applicable to or used with the present composites, articles, systems and methods. Therefore, the incorporated subject matter should not be used to limit the scope of the present disclosure. Summary of the invention

[0008] One aspect of the present disclosure is directed to a method comprising partially drying a liquid suspension of fibers and mixing the partially dried fibers with superabsorbent particles (SAP) such that at least some of the fibers are attached to at least some of the SAP to form fiber-SAP particles.

[0009] Another aspect of the present disclosure relates to an apparatus for forming superabsorbent particles with attached fibers. The apparatus includes: a fiber drying chamber having an inlet for supplying a supply of fiber-liquid suspension; and an atomizer located at the inlet, the inlet positioned to direct the atomized fiber-liquid suspension into the drying chamber. Partially dried fibers and liquid are received in the chamber. The apparatus includes a mixing chamber in communication with the drying chamber to receive the at least partially dried fibers from the drying chamber. The mixing chamber has an inlet for directing a supply of superabsorbent particles into the mixing chamber.

[0010] Another aspect of the present disclosure relates to a method of forming a superabsorbent particle (SAP) having a plurality of fibers attached thereto and extending outwardly from an outer surface thereof. The method includes introducing a fiber-liquid suspension into a first region by atomizing the liquid suspension and introducing partially spray-dried fibers and steam from the suspension into the first region. The method includes receiving the spray-dried fibers in a second region. The method includes introducing the SAP into the second region, including causing mixing of the SAP and the partially dried fibers therein. The fibers are supported on the SAP and extend therefrom.

[0011] One aspect of the present disclosure relates to a method of forming fiber-SAP particles. The method includes introducing fibers into a chamber and introducing superabsorbent particles (SAP) into the chamber. The fibers and SAP are mixed so that at least some of the fibers are attached to at least some of the SAP, forming fiber-SAP particles. In a further aspect, the fibers are introduced as a fiber-liquid suspension or introduced into a fiber-liquid suspension.

[0012] Other aspects of the present disclosure relate to fiber-SAP particles that include a superabsorbent core particle (SAP core particle) and a plurality of fibers attached to the SAP core particle.

[0013] A further aspect of the present disclosure relates to an absorbent composite comprising a substrate, a cover layer, and a fiber-SAP particle network located between the substrate and the cover layer. Each fiber-SAP particle comprises a superabsorbent core particle (SAP core particle) and a plurality of fibers attached to the SAP core particle.

[0014] Another aspect of the present disclosure relates to an absorbent article comprising a main body and an absorbent core composite supported on the main body. The absorbent core composite comprises a substrate, a cover layer, and a fiber-SAP particle network located between the substrate and the cover layer. Each fiber-SAP particle comprises a superabsorbent core particle (SAP core particle) and a plurality of fibers attached to the SAP core particle.

[0015] Another aspect of the present disclosure relates to a system for forming fiber-SAP particles. The system includes a chamber, a fiber input component (e.g., a spray drying device) positioned to introduce fibers into the chamber, and a SAP input component (e.g., a pipe, a supplier and / or a nozzle) positioned to introduce SAP into the chamber. The chamber includes a fiber / SAP mixing area and a fiber-SAP particle collection area located downstream of the fiber / SAP mixing area.

[0016] Another aspect of the present disclosure relates to a method for making a pulp-free absorbent material. The method includes providing microfibrillated cellulose fibers (MFC) and spray drying the MFC as a low concentration aqueous suspension into a fluidized bed containing superabsorbent (SAP) particles. The suspension includes a suspended liquid, which is water or a water / alcohol mixture. The method includes mixing the MFC fibers with the superabsorbent particles in a fluidized bed chamber. The mixing results in a plurality of fibers of the MFC being attached to each superabsorbent particle.

[0017] Another aspect of the present disclosure relates to a method for making a pulp-free absorbent material. The method includes providing microfibrillated cellulose fibers (MFC) and mixing the fibers with superabsorbent (SAP) particles. Mixing may include mixing MFC with superabsorbent particles in a liquid suspension so that a large number of fibers are attached to each superabsorbent particle. The attachment mechanism is that some residual water or alcohol in the chamber activates the surface of the SAP particles for fiber attachment. The method includes evaporating the residual liquid during the drying process after the mixing step. The dried mixture forms a finished mixture of MFC and SAP, and a large number of fibers are attached to the SAP particles. In some aspects, after the mixing step, the method includes feeding the dried finished material mixture of MFC and SAP directly onto a substrate into a diaper machine to form an absorbent core.

[0018] Another aspect of the present disclosure relates to a method for manufacturing a pulp-free absorbent material, the method comprising providing microfibrillated or nanofibrillated cellulose fibers (FC) and mixing the FC with superabsorbent particles. In some aspects, the FC is provided by spray drying, thereby removing liquid contents from the FC. The mixing of FC with SAP includes introducing FC into a fluidized bed containing superabsorbent (SAP) particles so that a large number of fibers are attached to each superabsorbent article. In some aspects, MFC and superabsorbent particles are mixed in a liquid suspension. The attachment mechanism is that some residual water or alcohol in the chamber activates the surface of the SAP particles for fiber attachment. The method may include evaporating the residual liquid in the drying process after mixing to form a finished mixture of MFC and SAP, which has a large number of fibers attached to each SAP particle. After the mixing step, the method includes feeding the dried finished material mixture of MFC and SAP directly onto a substrate into a diaper machine to form an absorbent core.

[0019] Another aspect of the present disclosure relates to a method for making a pulp-free absorbent material, which includes providing microfibrillated cellulose fibers, nanofibrillated cellulose fibers, or mixtures thereof (collectively referred to as "FC"), and mixing the fibers with superabsorbent (SAP) particles (e.g., in a mixing zone) so that a large number of fibers are attached to each superabsorbent particle. The FC can be in a liquid suspension, which can be provided by atomization, such as by spray drying. Spray drying produces water-based droplets. In some aspects, the FC is spray dried into a heated environment. Spray drying causes solid fibers to float in the air. In some aspects, the fibers are dry and less entangled after floating in a heated environment. In some aspects, SAP is introduced after spray drying and / or downstream thereof so that the fibers are attached to the surface of each SAP particle. In some aspects, the method includes mixing an additive with the FC and the SAP, optionally in a mixing zone downstream of the spray drying FC. The method includes collecting a mixture of FC-coated SAP after the mixing step, and optionally drying the mixture to remove residual liquid therefrom. In some aspects, drying includes removing residual liquid therefrom using infrared energy, hot air, or a fluidized bed approach. Although the embodiments shown and described herein use a spray drying method, in some aspects, the method may include a wet process using ultrasonic drying, or a solvent slurry of the fiber and subsequent drying and solvent recovery steps. Ultrasonic drying applies vibrations (e.g., at a resonant frequency) to the liquid suspension at ultrasonic frequencies, shear-thinning the liquid suspension, which allows the liquid suspension to flow more easily (e.g., through a nozzle). In some aspects, ultrasonic drying causes the fiber liquid suspension to be partially dried before atomization. Ultrasonic drying dehydrates the liquid suspension, giving the liquid suspension a greater degree of consistency before it is introduced into chamber 24. Those skilled in the art will appreciate that the liquid suspension is not limited to being introduced by spray drying or ultrasonic drying, but can be introduced by any method capable of atomizing the liquid suspension to form an aerosol thereof.

[0020] Other aspects of the present disclosure relate to absorbent materials including superabsorbent particles, each particle having a plurality of fibers attached to its outer surface.The fibers may be cellulose fibers, such as microfibrillated cellulose fibers, nanofibrillated cellulose fibers, or a combination thereof.

[0021] Some aspects of the present disclosure relate to a disposable absorbent article comprising a body and an absorbent core composite supported on the body. The absorbent core composite comprises a network of superabsorbent particles (SAP) with cellulose fibers attached to its outer surface. The fibers may be microfibrillated cellulose fibers, nanofibrillated cellulose fibers, or a combination thereof.

[0022] Another aspect of the present disclosure relates to a method for making absorbent particles. The method includes spray drying a liquid suspension of fibers in a solvent (e.g., water and / or ethanol) (e.g., into a fluidized bed chamber) so that the fibers interact with SAP. The liquid suspension may be spray dried in an initial or top layer in the fluidized bed chamber. Spray drying may include using an atomizer and a nozzle (gun) to introduce the liquid suspension into a heated environment or region in a heated spray layer of the method. Spray drying the liquid suspension increases the surface area of ​​the liquid suspension, at least partially drying the fibers of the liquid suspension. Spray drying the liquid suspension also increases the amount of steam moisture present in the fluidized bed chamber; thereby: (1) wetting the SAP surface; (2) causing an increase in the stickiness of the SAP surface; and (3) increasing the tendency of SAP to adhere to the fibers. The spray region of the fluidized bed chamber may be located upstream of a mixing region or layer of the fluidized bed chamber. At least some of the fibers adhere to the SAP to form fiber-SAP particles. At least a portion of at least some of the adhered fibers of the fiber-SAP particles extend from the SAP, perpendicular to the SAP surface. Some aspects include a mixed layer, in which SAP or SAP and additives are introduced and mixed with fibers. Some aspects include a collection layer, in which fiber-SAP particles are collected, optionally followed by a drying layer, in which the collected fiber-SAP particles are dried. In some aspects, fiber-SAP particles are incorporated into diapers, absorbent cores, or a combination thereof. Turbulent mixing can occur in a mixed region so that fibers at least partially dried are mixed with SAP. The flow path of the fibers introduced is generally perpendicular to the flow path of the SAP introduced. The mixed region or layer includes a nozzle or inlet for additive particles or ingredients. Some aspects of the method include controlling the flow or input of spray-dried fibers, SAP, and any additives. Adhesion between fibers and SAP occurs by bonding, hydrogen bonding, or other interactions between fibers and SAP.

[0023] In some aspects of the method, the fiber, SAP, fiber-SAP or a combination thereof is functionalized. The fiber may be functionalized before being introduced into the spray drying apparatus. The SAP may be functionalized before being introduced into the fluidized bed chamber. The fiber may include MFC fibers, nanofibrillated cellulose fibers, non-microfibrillated or nanofibrillated pulp fibers, textile fibers or a combination thereof.

[0024] In some aspects, the SAP is mixed with the additive before entering the fluidized bed chamber, the liquid suspension is mixed with the additive before entering the fluidized bed chamber, or a combination thereof. Regardless of when and how they are introduced, the additives introduced into the fluidized bed chamber may include metal ions, polyelectrolyte complexes, nanocellulose, clay bentonite particles, crosslinked particles, or a combination thereof.

[0025] The method may include a corona treatment layer, which may be located downstream of the spray drying layer and upstream of the collection layer. The corona treatment zone or layer may also be downstream of the mixing zone or at least partially overlap with it. The corona treatment induces one or more chemical reactions (e.g., crosslinking) in the fluidized bed chamber. Certain aspects of the method include a crosslinking step to crosslink at least the SAP surface.

[0026] In certain aspects of the method, the heated zone within the fluidized bed chamber is heated to a temperature above the ambient temperature of the fluidized bed chamber (eg, above room temperature).

[0027] The method may include wetting the surface of the SAP. The surface of the SAP may be wetted using steam formed by spray drying the liquid suspension, additional steam introduced into the fluidized bed chamber, or a combination thereof.

[0028] The method may include forming a channel from the surface of the SAP to the interior of the SAP with fibers. For example, during mixing, bonding and / or bonding, at least some of the fibers may be at least partially embedded in the surface of the SAP particles so that the embedded fibers extend to the interior of the SAP particles, below the surface of the SAP particles. The embedded fibers can be used as a channel to introduce fluid into the interior of the SAP particles.

[0029] In some aspects, wicking channels or pathways are formed between adjacent fiber-SAP particles.

[0030] In some aspects, the fiber-SAP particles are incorporated into a diaper, an absorbent core, or a combination thereof.

[0031] Another aspect of the present disclosure relates to fiber-SAP particles, which include SAP particles and a plurality of fibers attached to the SAP particles. At least a portion of at least some of the fibers extends from the SAP particles, perpendicular to the outer surface of the SAP particles. At least some of the fibers may be at least partially embedded in the SAP, providing a path or channel to the interior of the SAP; thereby increasing the absorption rate of the SAP. Liquid may be absorbed into the embedded fibers and flow within the fibers into the interior of the SAP. In some aspects, the surface of the fiber-SAP particles is at least partially cross-linked. The fibers attached to the SAP may have a length shorter, equal, or longer than the average diameter of the SAP particles.

[0032] Another aspect of the present disclosure relates to an absorbent article comprising a plurality of fiber-SAP particles incorporated therein. The fibers attached to the SAP can act as a buffer; thus, causing less compression of the SAP during use and maintaining the swellability of the SAP. Adjacent fiber-SAP particles in the article can remain at least partially spaced apart, forming wicking paths between adjacent fiber-SAP particles. The wicking paths allow fluid to flow therebetween.

[0033] Another aspect of the present disclosure relates to a fiber-SAP particle, which includes a SAP particle core and a plurality of fibers extending from the SAP. Each fiber has a first end bonded, attached, adhered or otherwise joined to the SAP, and a free end not bonded, attached, adhered or otherwise joined to the SAP.

[0034] Certain aspects of the present disclosure provide methods and systems for forming a structural unit, the structural unit comprising or consisting of SAP and MFC (or another fiber). In such a structural unit of SAP and MFC (i.e., fiber-SAP particles), SAP and MFC are closely connected (i.e., a single component rather than two components meant to be mixed together) and work synergistically during use to provide absorbency and other absorbent product functions.

[0035] Certain aspects of the present disclosure provide methods and systems for producing fiber-SAP particles that use low levels of solvents / liquids during their formation. Due to the low solvent content of the components introduced into the reaction zone (e.g., fluidized bed chamber), the methods and systems that use low levels of solvents / liquids eliminate or at least reduce the use of drying, solvent recovery processes, and other such process steps associated with wet processes / systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Therefore, the manner in which the features and advantages of the embodiments of the present disclosure may be understood in more detail, a more particular description of the embodiments briefly summarized above may be obtained by reference to the embodiments illustrated in the accompanying drawings which form a part of this specification. However, it should be noted that the accompanying drawings only illustrate various exemplary embodiments and therefore should not be considered to limit the scope of the present disclosure, as it may also include other effective embodiments.

[0037] Figure 1 is a simplified illustration of an apparatus and method for making absorbent material according to the present disclosure;

[0038] Figure 1A is a simplified illustration of a collection area or device according to the present disclosure;

[0039] Figure 2 is a simplified illustration of a fiber-SAP particle according to certain aspects of the present disclosure;

[0040] Figure 2A is a simplified illustration of a swollen fiber-SAP particle according to certain aspects of the present disclosure;

[0041] Figure 2B According to some aspects of the present invention, after drying Figure 2A A simplified illustration of a fiber-SAP particle;

[0042] Figure 2C and 2D is a scanning electron microscope (SEM) image of SAP;

[0043] Figure 3 is a simplified illustration of two adjacent fibrous SAP particles according to certain aspects of the present disclosure;

[0044] Figure 3A is a simplified illustration of a fiber-SAP particle network according to certain aspects of the present disclosure;

[0045] Figure 4 Diapers according to certain aspects of the present disclosure are depicted.

[0046] Figure 5A and 5B is a flow chart of a method of making fiber-SAP particles according to certain aspects of the present disclosure;

[0047] Figure 6 is a flow chart of a method of making fiber-SAP particles according to certain aspects of the present disclosure;

[0048] Fig. 6A is a flow chart of a method of making fiber-SAP particles according to certain aspects of the present disclosure;

[0049] Figure 7 is a simplified illustration of an absorbent core according to certain aspects of the present disclosure;

[0050] Fig. 8A and 8B is a simplified illustration of a system including multiple zones according to certain aspects of the present disclosure;

[0051] Fig. 9 is a schematic flow diagram of a method for making fiber-SAP particles according to certain aspects of the present disclosure;

[0052] Fig. 10A is a schematic diagram of an apparatus for making fiber-SAP particles according to certain aspects of the present disclosure;

[0053] Fig. 10B is along Fig. 10A A cross-sectional view of line AA in FIG. 1 ; and

[0054] Fig.11 is a schematic diagram of an apparatus for forming fibrous particles showing flow paths for various inputs and outputs, including an air jet flow path. DETAILED DESCRIPTION

[0055] Embodiments of the present disclosure will now be described more fully with reference to the accompanying drawings, which illustrate various exemplary embodiments. However, the disclosed concepts can be implemented in many different forms and should not be construed as being limited by the illustrated embodiments set forth herein. On the contrary, these embodiments are provided to make the present disclosure thorough and complete, and will fully convey the scope and best mode of practicing the embodiments to those skilled in the art. For example, many exemplary descriptions provided herein relate to absorbent materials for incorporation into diapers and training pants for infants and young children. However, the aspects of the present disclosure described may be equally applicable to the design and manufacture of other products. However, one group of applications relates to manufacturing absorbent materials that are very suitable for direct incorporation as core composites of absorbent articles (e.g., diapers or training pants). Methods and products can be directly and linearly incorporated into or as a core forming stage of a substantially linear system and a method for manufacturing such absorbent articles.

[0056] Disposable absorbent articles contemplated in the present disclosure include, but are not limited to, training pants, pull-on diapers, disposable underpants, and adult incontinence garments. As for training pants, these garments may be used by young children to facilitate the child's transition from using diapers to wearing regular underpants (i.e., during toilet training). Training pants and other disposable pull-on pants may have closed sides, allowing the user or caregiver to lift the garment around the user's legs to put on the garment and slide the garment down around the user's legs to remove it. These articles and garments are collectively referred to herein as "absorbent pants" or "pants products."

[0057] As Suzuki'294 teaches and describes, microfibrillated fibers and methods for making them provide suitable raw materials or raw material sources for certain aspects of the present method. It should be noted that although Suzuki'294 prior patent disclosures provide some discussions about manufacturing MFC and then incorporating it into absorbent articles, the present disclosure is more specifically related to providing improved systems and methods for manufacturing absorbent articles, core composites and / or absorbent materials in at least one aspect. More specifically, an instruction of the present disclosure is to provide a method and system, whereby and in which fibers or cellulose products / fiber networks and their formation are seamlessly integrated into the method for manufacturing articles and the absorbent material itself. On the other hand, Klemp'557 discloses that exemplary product applications and core designs can be provided, and products of certain aspects of the present disclosure may be suitable for them. According to one aspect of the present disclosure, the microfibrillated cellulose prepared as Suzuki'294 teaches is spray-dried as a low consistency aqueous suspension into a fluidized bed containing superabsorbent particles (SAP). For example, the suspended liquid can be water or a water / alcohol mixture. According to this aspect, the mixing of microfibrillated cellulose with superabsorbent particles in the fluidized bed chamber results in a large number of fibers attached to each superabsorbent particle. The attachment mechanism may be caused by some residual water or alcohol in the chamber, which activates the SAP particle surface for fiber attachment. This residual liquid is evaporated in a subsequent drying process. The dried finished material can then be fed directly into a diaper machine to form the absorbent core of a finished diaper.

[0058] The fibers according to the present method and product can be microfibers, nanofibers or combinations thereof. As used herein, "micro" with respect to fibers refers to fibers having an average diameter of 100 to 1000 nanometers, or 200 to 900 nm, or 300 to 800 nm, or 400 to 700 nm, or 500 to 600 nm; and fibers having an average length of at least 1 micron to several microns. As used herein, "nano" with respect to fibers refers to fibers having an average diameter generally in the range of about 10 to about 100 nm, or about 20 to about 90 nm, or about 30 to 80 nm, or 40 to 70 nm, or 50 to 60 nm; and fibers having an average length of 50 to 3,000 nm, or 100 to 2500 nm, or 200 to 2000 nm, or 300 to 1500 nm, or 400 to 1000 nm, or 500 to 900 nm, or 600 to 800 nm. As will be appreciated by those skilled in the art, fiber size is typically measured using optical or electron microscopy.

[0059] The resulting fiber-coated SAP (fiber-SAP) is particularly suitable for producing pulp-free absorbents for diapers and other hygiene products. Microfibrillated cellulose is hydrophilic, and the fiber bundles on the SAP surface allow faster absorption of liquid into the particles compared to other identical SAPs that are not coated or attached to fibers (i.e., not fiber-SAP); liquid is better distributed from particle to particle than other identical SAPs that are not coated or attached to fibers (i.e., not fiber-SAP); SAP absorbs better under load than other identical SAPs that are not coated or attached to fibers (i.e., not fiber-SAP); and SAP is better fixed due to higher particle-particle interactions than other identical SAPs that are not coated or attached to fibers (i.e., not fiber-SAP). In some aspects, the absorbent materials disclosed herein do not include any absorbent matrix other than the fibers attached to the SAP core particles.

[0060] System / device for producing fiber-SAP granules

[0061] An exemplary system suitable for producing the fiber-SAP particles disclosed herein will now be briefly described. Certain aspects of the present disclosure relate to systems and apparatus for forming fiber-SAP particles. Figure 1, the fiber-SAP forming system 9000 includes a fiber-SAP forming device 100, including a fluidized bed chamber 101. The inner cavity of the fluidized bed chamber 101 defines a chamber 24. The device 100 includes a fiber input device, shown here as a spray drying device 20, which includes an atomizer and a nozzle (gun) 22. A fiber supplier, shown here as an MFC supplier 103, provides a liquid suspension of fibers 10 to the atomizer and the nozzle (gun). Coincident with the spray drying device 20 and / or downstream of the spray drying device 20, the fluidized bed chamber 101 includes a spray zone 31, which can be a heated spray zone. Coincident with the spray zone 31 and / or downstream of the spray zone 31, the fluidized bed chamber 101 includes a mixing zone 33. Coincident with the mixing zone 33 and / or downstream of the mixing zone 33, the fluidized bed chamber 101 includes a corona treatment zone 29. Downstream of the mixing zone 33, the fluidized bed chamber 101 includes a collection zone 26. The device 100 includes a SAP supplier 105 and an optional additive supplier 107, which can overlap with the mixing area 33, supplying SAP 16 and additive 18 respectively. Downstream of the collection area 26, the system 9000 includes a system or device for forming an absorbent core 8000 using fiber-SAP particles 19. Downstream of the system or device for forming the absorbent core 8000, the system 9000 includes a system or device for forming an absorbent article 7000 using the absorbent core formed in the system 8000. For the sake of clarity, systems 8000 and 7000 are not described in detail herein. However, those skilled in the art will understand that systems 8000 and 7000 can be any system suitable for forming absorbent cores and absorbent articles, and in fact, can be a single system, rather than two separate systems as shown. For example, Suzuki '294 discloses a suitable system and method for producing absorbent cores and articles using SAP particles, which can be suitable for use with the fiber-SAP particles 19 disclosed now. In some aspects, the dry finished absorbent material (ie, the dry fiber-SAP particles 19 or network thereof) is fed directly into a diaper machine to form an absorbent core for finished diapers without any intermediate processes in between.

[0062] Now that an exemplary system for forming fiber-SAP particles has been described, reference will now be made to Figure 1 The system describes a method for forming fiber-SAP particles.

[0063] Spray drying

[0064] refer to Figure 1Fibers (e.g., cellulose fibers) are introduced into chamber 24 in such a manner that the fibers are dispersed and / or spread within chamber 24. For example, the fibers may be introduced so that an aerosol (i.e., a colloid of fibers and optional liquid droplets in air or another gas) is formed, with the fibers suspended in the air or other gas within chamber 24. One example of such a method of introducing the fibers is spray drying. This presents the fibers in a liquid suspension 10, which is then atomized so that liquid-based droplets 12 are generated and dispersed within chamber 24. Atomization of the liquid suspension 10 allows all or substantially all of the liquid of the liquid suspension to readily flash the fibers into the surrounding environment within chamber 24. Such flashing of liquid is a convenient way to reduce the volume or amount of liquid in a finished or near-finished absorbent product, which can be dried or removed in a subsequent layer.

[0065] The introduction of the liquid suspension 10 of the fibers occurs by spraying the initial or top layer in the upper region of the chamber 24. In some aspects, the liquid suspension 10 is a slurry of fibers and a solvent (MFC slurry). The solvent may be water, a low molecular weight alcohol (e.g., ethanol and / or isopropanol), another solvent, or a combination thereof. Ethanol and other low molecular weight alcohols may not induce a high degree of swelling of the SAP like water, evaporate at a lower temperature than water, dry faster from the fibers than from water, and have a lower viscosity than water. The atomizer and nozzle (gun) 22 can introduce the liquid suspension 10 into a heated environment or region of the device 100, such as into a heated spray region or layer 31. The heated region can be heated to be sufficient to promote evaporation of the liquid from the fibers. For example, if the liquid is water, the heated region can be at a temperature of at least 100°C, or a temperature of 180°C to 200°C. In some aspects, heated air is recirculated in the mixing chamber 33 for evaporating the liquid from the fibers. Spray drying the liquid suspension 10 increases the surface area of ​​the liquid suspension 10, at least partially drying the fibers of the liquid suspension 10 within the chamber 24. Moreover, spray drying the fibers can increase the amount of vapor moisture present in the chamber 24 relative to the amount of vapor moisture present in the chamber 24 prior to spray drying the liquid suspension 10, as a result of the liquid being introduced as additional vapor moisture. The increase in vapor moisture in the chamber 24 can result in surface wetting of the SAP 16 present in the chamber 24 (i.e., moisture (e.g., water) is deposited onto the outer surface of the SAP 16). Such wetting of the outer surface of the SAP 16 can result in an increase in the viscosity of the outer surface of the SAP (e.g., increased H-bonding) relative to the viscosity of the outer surface of the SAP prior to wetting, which increases the propensity of the SAP 16 to attach (e.g., H-bond) to the fibers of the liquid suspension 10.

[0066] In some aspects, the liquid suspension of fibers comprises greater than 0% to 30% by weight of fibers, or 5% to 20% by weight of fibers, or 10% to 15% by weight of fibers, based on the total weight of the liquid suspension. In certain aspects, the liquid suspension of fibers comprises up to 20% by weight of fibers, or 0.1% to 10% by weight of fibers, or 1% to 8% by weight of fibers, or 2% to 7% by weight of fibers, or 3% to 5% by weight of fibers, based on the total weight of the liquid suspension.

[0067] Regardless of the particular form of introduction used to aerosolize the liquid suspension, the fibers and liquid are a single component when forming the aerosol, rather than separate components.

[0068] In some aspects, coincident with or downstream of the spray drying zone (or other introduction method), an initial layer of pre-drying of the fibers of the liquid suspension occurs to reduce the liquid content of the fibers. In this pre-drying zone, the liquid suspension of fibers is atomized and dynamically moved within chamber 24 to promote and maintain separation of the individual fibers of the fiber liquid suspension and prevent aggregation or agglomeration thereof. This dynamic movement also promotes drying (e.g., evaporation) of the liquid from the fibers and into the surrounding environment (e.g., into the air within chamber 24).

[0069] Mixed Area

[0070] The spray zone of the device 100 may be located above and / or upstream of the mixing zone or layer 33 of the device 100. In the mixing zone 33, turbulent mixing may be promoted and / or encouraged, and the nearly dry (dry and / or less entangled) fibers may be mixed with the supplied superabsorbent particles 16. In some aspects, turbulent mixing may be promoted and / or encouraged by introducing the SAP 16 into the chamber 24 at an angle greater than 0 degrees relative to the direction in which the liquid suspension 10 is introduced into the chamber 24, for example, at an angle ranging from 15 degrees to 180 degrees, or from 20 degrees to 150 degrees, or from 40 degrees to 120 degrees, or from 60 degrees to 100 degrees, or from 70 degrees to 90 degrees. In addition, such turbulent mixing may be promoted by using a nozzle to introduce one or more of the liquid suspension 10, the SAP 16, and the additive 18, using heat, or a combination thereof. The SAP 16 may be introduced through the sidewalls of the chamber 24 and generally perpendicular to the supplied fibers (i.e., the liquid suspension 10), such as through an inlet, conduit, and / or one or more nozzles engaged with and / or passing through the sidewalls of the chamber 24. In some aspects, the device 100 may be equipped with additional inlets, conduits, and / or nozzles at the mixing region or layer 33 for introducing additive particles 18 or ingredients into the chamber 24. Within the mixing region 33, the fibers are deposited on or otherwise attached to the SAP 16 particles. For example, the SAP 16 may be introduced into the fiber aerosol so that the SAP is intermixed with the fibers within the fiber colloid.

[0071] The device 100 can allow the flow or input of the spray-dried fibers, SAP 16, and additives 18 to be controlled at any time, for example, by using valves and nozzles, and manual and / or automatic controllers for these valves and nozzles; therefore, a batch of finished product chemical compositions is possible and the mechanical and physical properties of the fiber-SAP particles are obtained. In some aspects, the air flow is guided to keep the fibers, SAP, and any other components suspended in the air in the chamber 24 mixed in the chamber 24. The air flow can be controlled and / or guided to allow the fiber-SAP particles 19 to settle and collect when they are dried and mixed together. The constant stirring of the SAP and fibers caused by turbulent mixing minimizes agglomeration during the drying process. In some aspects, the air flow is provided and / or controlled by one or more fans, which are positioned to provide an air flow into the chamber 24. The fan can be configured and / or arranged to provide a vortex in the chamber 24.

[0072] Thus, in some aspects, the fibers are pre-dried, the SAP is wetted and thereby activated, and the pre-dried fibers and wetted SAP are mixed together to adhere to each other in a single reaction chamber.

[0073] Collection Area

[0074] Below and / or downstream of the mixing zone 33, a volume, network, or collection of fiber-coated SAP (fiber-SAP) 19 is concentrated and / or collected at a collection region or layer 26 of the device 100. The collection region 26 is located at the bottom of the chamber 24; however, those skilled in the art will appreciate that the device 100 is not limited to this configuration. The fiber-coated SAP 19 settles within the collection region 26, which may be isolated from the turbulence of the mixing zone 33. Within the collection region 26, the fiber-SAP particles 19 form a higher density of these components relative to the density of the group or collection of fibers, SAP, fiber-SAP 19, or combinations thereof within the mixing zone 33. Within the collection region 26, individual fiber-SAP particles 19 are positioned adjacent to other individual fiber-SAP particles 19 so that adjacent individual fiber-SAP particles 19 interact, contact, or otherwise engage with each other. Such interactions between adjacent fiber-SAP particles 19 may involve interactions between fibers of the fiber-SAP particles 19, interactions between fibers of one fiber-SAP particle 19 and the SAP of an adjacent fiber-SAP particle 19, interactions between the SAP of the fiber-SAP particles 19, or a combination thereof. Once settled in the collection area 26, a network of fiber-SAP particles 19 is formed. The network of fiber-SAP particles 19 may optionally be dried to remove any residual liquid therefrom. Such drying may be facilitated by heat, air flow, residence time in the collection area 26, or a combination thereof.

[0075] In some aspects, the process is a batch process in which the fiber-SAP particles 19 are collected in batches (eg, manually) in a collection area and removed therefrom.

[0076] In other embodiments, the process is a continuous process or a semi-continuous process. Figure 1A , showing a collection area 26b of a continuous process. The collection area 26b may include a conduit or chamber having a length L, a flow path V, and a temperature T associated therewith, sufficient to allow the fiber-SAP particles 19 to have a residence time in which they dry when entering the settling tank below the conduit or chamber. The flow path V may be controlled at least in part by a flow nozzle and / or a circulating jet in fluid communication with the conduit or chamber. For example, the temperature T may be controlled by one or more heating elements. Therefore, the collection area 26b may be an extended chamber dryer to ensure that the fiber-SAP particles 19 are dry when pumped therefrom by a pump P. Those skilled in the art will appreciate that other system and device configurations and arrangements may be used to selectively separate fiber-SAP particles from pre-wetted partially swollen SAP particles in a continuous process. This separation method may rely on differences in density, resistance, weight, particle size, other properties, or combinations thereof, to selectively output or remove fiber-SAP particles rather than pre-wetted partially swollen SAP particles. This separation method may utilize a vortex or circumferential flow that guides selected particles to an outlet. Such a flow may be provided by jets directing the flow of air.

[0077] Corona treatment area

[0078] In some aspects, the apparatus 100 includes a corona treatment zone or layer 29, which may be downstream of the spray drying device 20 and upstream of the collection zone 26. The corona treatment zone or layer 29 may be downstream of or at least partially coincident with the mixing zone or layer 33. Corona treatment of the fibers, SAP 16, and / or fiber-SAP particles 19 may initiate one or more chemical reactions within the chamber 24. Those skilled in the art will appreciate that the apparatus 100 may include other chemical, thermal, and / or physical treatment zones or layers in addition to or in place of the corona treatment zone or layer 29. The corona treatment may promote bonding between the fibers and the SAP 16.

[0079] In some aspects, the corona charges the SAP surface to make the SAP more hydrophilic (i.e., activates the SAP surface to wet (makes the SAP wettable)), promotes ionization of the components within the chamber, initiates cross-linking of SAP molecules with other SAP molecules, initiates cross-linking of fiber molecules with other fiber molecules, initiates cross-linking of SAP molecules with fiber molecules, or initiates other chemical reactions between the components within chamber 24.

[0080] Cross-linking

[0081] In some aspects, the outer surface of SAP 16 and / or fiber-SAP particles 19 can be at least partially cross-linked, which can reduce gel blocking when fiber-SAP particles 19 absorb liquid. In some aspects, cross-linking on the surface of fiber-SAP particles 19 can be induced by corona treatment. In some aspects, the outer surface of SAP 16 introduced into chamber 24 can be at least partially cross-linked before introduction into chamber 24, and corona treatment can be used to further (e.g., completely) cross-link the outer surface of SAP 16. In other aspects, the outer surface of SAP 16 introduced into chamber 24 can be not cross-linked before introduction into chamber 24, and corona treatment is used to cross-link the outer surface of SAP 16 that was not cross-linked before. In still other aspects, the outer surface of SAP 16 introduced into chamber 24 can be completely cross-linked before introduction into chamber 24, and corona treatment is not used to further cross-link the outer surface of SAP 16.

[0082] In some aspects, the SAP introduced into chamber 24 is not crosslinked, or is partially crosslinked, when introduced into chamber 24. In some such aspects, the SAP is subsequently crosslinked within chamber 24, such as by introduction of crosslinking particles, corona treatment, or a combination thereof. In some aspects, the SAP is not fully crosslinked when introduced into chamber 24. In certain aspects, the SAP does not have a core-shell morphology, such that the SAP does not include an outer shell or surface that is more crosslinked than an inner core that is less crosslinked.

[0083] In some aspects, the fiber-SAP particles 19 include: (1) crosslinks between polymer chains of the SAP core particles and other polymer chains of the SAP core particles; (2) crosslinks between polymer chains of the SAP core particles and polymer chains of the fibers; (3) crosslinks between polymer chains of the fibers and other polymer chains of the fibers; or (4) combinations thereof.

[0084] Fiber-SAP Bonding

[0085] Bonding between the fibers and SAP 16 to form the fiber-SAP particles 19 may occur within the mixing zone 33, downstream of the mixing zone 33 but upstream of the collection zone 26, within the collection zone 26, downstream of the collection zone 26, or a combination thereof. For example, in some aspects, the fibers are coated onto the SAP 16 but not yet bonded to the SAP 16 when mixed in the mixing zone 33 and / or when collected within the collection zone 26. Bonding between the fibers and the SAP 16 may be facilitated by drying, such that when the fiber network and the SAP 16 within the collection zone 26 dry, the fiber-SAP particles 19 are formed. Bonding between the fibers and the SAP 16 may occur by: bonding the fibers to the surface and / or interior of the SAP 16; hydrogen bonding of the fibers to the surface and / or interior of the SAP 16; polymer chain entanglement of the polymer chains of the fibers and the polymer chains of the SAP 16; or other forms of bonding, entanglement, adhesion, partial dissolution, attachment, engagement, or other interactions between the fibers and the SAP 16.

[0086] In some aspects, turbulence within the mixing region 33 promotes significant relative movement of SAP 16 and any fibers attached to SAP 16. This turbulence causes the unattached portions (free ends) of the attached fibers to be lifted from the surface of SAP 16. Additionally, this turbulence promotes drying of SAP 16 and any fibers attached thereto, further strengthening the attachment between the fibers and SAP 16. Whether or not the fibers are embedded in SAP 16, the fibers attached to SAP 16 provide a path for fluid to flow to SAP 16 because the high surface area of ​​the fibers provides additional surface area for absorption if contaminated (relative to the surface area of ​​the SAP alone).

[0087] Functionalization

[0088] In some aspects, the fibers, SAP 16, fiber-SAP 19, or a combination thereof are functionalized. For example, the fibers can be functionalized (e.g., grafted) prior to introduction into the spray drying apparatus or after introduction into chamber 24. In some aspects, SAP 16 can be functionalized (e.g., grafted) prior to or after introduction into chamber 24. In some aspects, additive 18 chemically reacts with the fibers and / or SAP 16 to functionalize the fibers and / or SAP 16.

[0089] In some aspects, functionalization (functional groups) applied (e.g., bonded) to the fibers, such as ion exchange or odor reduction functional groups or particles, act on the dirt (e.g., liquid dirt) before the dirt is absorbed and captured by the SAP core particles. Thus, if the fibers are functionalized with ion exchange properties, the dirt can flow into the core SAP particles at a lower ionic strength, which provides the SAP with a higher dirt absorption capacity. If the fibers are functionalized with odor reduction functional groups or particles, the dirt can flow into the core SAP particles with a lower likelihood of generating malodor.

[0090] additive

[0091] Additives 18 may be introduced to mix and / or react with the fibers and / or SAP 16 to impart properties to the fiber-SAP particles 19 that can be used in sanitary products. The additives 18 may be mixed and / or reacted with the fibers before or after the fibers are introduced into the chamber 24; the additives 18 may be mixed and / or reacted with the SAP 16 before or after the SAP 16 is introduced into the chamber 24; the additives 18 may be mixed and / or reacted with the fiber-SAP particles 19 within the device 100 or downstream thereof; or a combination thereof. For example, but not limited to, the additives 18 may include metal ions for antimicrobial and odor reduction properties; polyelectrolyte complexes that may increase cation exchange capacity, which may increase the absorption capacity of the SAP by removing multivalent ions from urine; clay bentonite particles; cross-linked particles; other functional additives, such as, for example, using nanocellulose, which may provide biosensing functions; or a combination thereof. In some aspects, the additives include carbon (e.g., activated carbon), ion exchange resins, or agar. The additives 18 may include one or more adhesion promoters to promote adhesion between the fibers and the SAP.

[0092] In some aspects, the fibers are treated (e.g., pretreated prior to spray drying) with one or more additives. For example, the fibers can be pretreated by combining the fibers with additives, including but not limited to: odor control additives, such as metal ions, such as copper (Cu +2 ), silver (Ag +1 ), gold ions (Au +1 and Au +3 ), iron (II) ions (Fe +2 ), iron (III) ions (Fe +3 ), permanganate ion (MnO4 -1 ) or a combination thereof; antimicrobial additives such as silver ions and copper (such as cuprous oxide-based additives); additives with ion exchange capabilities; or a combination thereof. Multivalent ions reduce the ionic strength of urine and increase SAP absorption capacity (e.g., grafted polyacrylic acid (PAA) or polyitaconic acid (PIA) acid).

[0093] fiber

[0094] In some aspects, the fibers of the liquid suspension 10 include MFC fibers, nanofibrillated cellulose fibers, non-microfibrillated or nanofibrillated pulp fibers, textile fibers, or a combination thereof. In some aspects, nanofibrillated cellulose or a mixture of microfibrillated and nanofibrillated cellulose can be used. Nanofibrils of nanofibrillated cellulose can have a higher surface area than fibers of microfibrillated cellulose.

[0095] Although the fiber is described as cellulose fiber herein, it will be understood by those skilled in the art that the fiber can be other non-cellulose fibers, such as other hydrophilic fibers. Moreover, the fiber can be a mixture of fibers of different types and / or sizes (e.g., a mixture of different hydrophilic fibers and / or a mixture of microfibers and nanofibers). In some aspects, in addition to or in place of cellulose, the fiber can include starch-based polymer fibers (e.g., polysaccharide fibers), polyethylene terephthalate (PET) fibers, polyethylene (PE) fibers, polypropylene (PP) fibers, alternative cellulose fibers (e.g., cotton fibers, bamboo fibers, flax fibers).

[0096] In some aspects, using nanometer-sized fibers (e.g., nanofibrillated cellulose fibers) provides more fiber surface area per unit weight of fibers attached to the outer surface of SAP. The fluid flow properties provided by the fibers are surface phenomena, so that dirt flows along the fiber surface to be introduced into the SAP core particles. Therefore, more fiber surface area per unit weight of fibers attached to the outer surface of SAP is provided, increasing the flow of dirt fluid to the SAP core particles.

[0097] Some advantages of this method

[0098] Some aspects of the methods according to the present disclosure provide one or more of the following additional advantageous results: (1) less energy is required to dry or reduce the water content due, at least in part, to the use of atomization and optional heating chamber 24; (2) more uniform mixing and distribution of the SAP or fibers is achieved due, at least in part, to the use of spray drying to mix the fibers and SAP; (3) a means is provided to more easily adjust or design the properties or chemical, mechanical and physical characteristics of the absorbent material; (4) easier manipulation of the mixture components (e.g., SAP, fibers, additives), including the selection of sequential or simultaneous addition of components, fiber-SAP ratios and / or additives. For example, the properties and characteristics of the absorbent material may be affected by one or more of the following: (1) the selection of fiber size, including fiber length and width (e.g., using microfibers and / or nanofibers); (2) fiber properties, including fiber size; (3) the selection of the fiber to SAP ratio; (4) optional functionalization of the fibers and / or SAP, such as by chemically bonding one or more functional groups to the fibers and / or SAP; and (5) the selection of additives to be combined with the fibers and SAP. Those skilled in the art will appreciate that these and other parameters can be varied to alter the chemical, physical, and / or mechanical properties of the resulting fiber-SAP particles.

[0099] The resulting fiber-SAP composite provides the fiber network with one or more of the following: (1) increased surface (absorbent) area or fiber exposure, thereby enhancing fluid absorption performance; (2) increased fluid distribution between the SAP and the fibers; (3) faster absorption rate; (4) more physical / mechanical interactions between the fiber-coated SAP particles, thereby enhancing fluid distribution and absorption performance and / or reducing SAP migration (i.e., inhibiting migration of the SAP during manufacture of the absorbent article and inhibiting channeling after manufacture).

[0100] Fiber-SAP particles

[0101] refer to Figure 1 and Figure 2In some aspects, the fiber-SAP particles 19 include a plurality of fibers 21a bonded (e.g., hydrogen bonded, ionically bonded, covalently bonded), attached, adhered, entangled, coated, or otherwise joined to SAP 16. At least some of the plurality of fibers 21a include a restricted end 45b (i.e., the end of the fiber 21a that is in some way joined to SAP 16) and a free end 45a that is free to move relative to SAP 16. The restricted end 45b is bonded, attached, adhered, embedded, or otherwise joined to and in contact with the outer surface 25 of SAP 16. The free end 45a is not directly bonded, attached, adhered, embedded, or otherwise joined to (and, in at least some configurations, does not contact) SAP 16 or its outer surface 25. The free end of each fiber 21 can be separated from SAP 16 by a distance. The free end of each fiber 21 can be free to move in at least one direction relative to SAP 16. Although described as being spaced apart from SAP 16, those skilled in the art will appreciate that free end 45a may have a range of free movement that allows free end 45a to contact SAP 16. In some aspects, free end 45a is free to move in at least one direction relative to SAP 16, but remains "tethered" to SAP 16 via restraining end 45b. As used herein, "free end" refers to the end of a fiber 21 of a SAP core particle 16 that is not directly attached to a fiber-SAP particle 19. Such a "free end" of a fiber 21 is free to move relative to the outer surface 25 of the SAP core particle 16.

[0102] In some aspects, fiber-SAP 19 may include one or more fibers 21b at least partially embedded in SAP 16, thereby providing a path or channel 17 into the interior of SAP 16. Such a path or channel 17 can increase the absorption rate of SAP 16. For example, Figure 2 The illustrated fiber-SAP 19 includes at least one fiber (fiber 21b) at least partially embedded in SAP 16, such that at least a portion of fiber 21b extends into the interior of SAP 16, past an outer surface 25 of SAP 16. In some such aspects, liquid (e.g., urine) can be absorbed into fiber 21b and flow within fiber 21b into interior 23 of SAP 16.

[0103] Whether or not the fibers are embedded in the SAP, the fibers 21 attached to the SAP 16 provide a path for dirt (e.g., urine) to flow along the fiber surface toward the SAP 16 for absorption therein, wherein the SAP acts as a pump, drawing liquid from the fibers. In some aspects, the embedded fibers can provide more contact surface area between the SAP and the fibers, enhancing the pull of dirt into the SAP through the fibers. Without being bound by theory, the embedding of the fibers can provide a more stable and / or rigid attachment between the fibers and the SAP, maintaining the associated fluid flow therebetween in a more consistent and reliable manner.

[0104] In some aspects, at least some of the fibers 21 attached to SAP 16 have at least a portion extending perpendicular to the outer surface 25 of SAP 16, or at least have a free range of motion relative to SAP 16 such that they can extend perpendicular to the outer surface 25 of SAP 16. In some aspects, a plurality of fibers 21 generally extend outward from the outer surface 25 of SAP 16. Such fiber-SAP particles 19 may be described as "fuzzy particles" or "fuzzy particles" having a particle core (i.e., SAP 16) bonded, attached, adhered, or otherwise joined to a plurality of fibers 21 such that the free ends of the fibers 21 extend from SAP 16. In certain aspects, the fibers 21 attached to SAP 16 may have a length that is shorter, equal to, or longer than the average diameter of the SAP 16 particles.

[0105] Embedding mechanism

[0106] As referenced above Figure 2 and Figure 3 In some aspects, at least some fibers are embedded in the core SAP particles. When attached between the fiber and the SAP (e.g., in the mixing area of ​​the chamber), the presence of moisture in or on the fiber and / or in or on the SAP causes the outer surface of the SAP to swell and / or soften (i.e., the SAP absorbs moisture, causing the SAP to swell and soften). The presence of moisture in or on the fiber and / or in or on the SAP also promotes the "stickiness" of both the fiber and the SAP, and encourages the fiber and the SAP to "stick" together. For example, if the moisture is water, the presence of water in or on the fiber and / or in or on the SAP promotes hydrogen bonding between the fiber and the SAP. The swelling and / or softening of the outer surface of the SAP encourages the fiber to attach to it. In some aspects, the swelling and / or softening of the SAP is sufficient to form nano or micro cracks on the surface of the SAP, so that a portion of the fiber can be embedded in these cracks and attached to the SAP. The subsequent drying of the fiber and the SAP causes the corresponding shrinkage and / or hardening of the SAP; thereby, the fiber is kept in a suitable position on the SAP and / or embedded in the SAP. Such embedded fibers penetrate the outer surface of the SAP at least some distance into the SAP.

[0107] In some aspects, each fiber-SAP particle has 10 to 60 wt% of fibers attached thereto, or 20 to 50 wt% of fibers attached thereto, or 30 to 40 wt% of fibers attached thereto (each based on the total weight of the fiber-SAP particle). In certain aspects, each fiber-SAP particle has 0.1 to 30 wt% of fibers or 0.5 to 15 wt% of fibers based on the total weight of the fiber-SAP particle.

[0108] Fiber-SAP particle interaction

[0109] refer to Figure 3 , adjacent fiber-SAP particles 19a and 19b can remain at least partially spaced apart, so that one or more fibers 21 of adjacent fiber-SAP particles 19a and 19b can contact or entangle with each other. In some aspects, one or more fibers 21 of adjacent fiber-SAP particles 19a and 19b can be bonded to each other (e.g., hydrogen bonded). In other aspects, the fibers 21 of adjacent fiber-SAP particles 19a and 19b do not contact, entangle or bond with each other. In some aspects, the SAP 16 of adjacent fiber-SAP particles 19a and 19b does not contact. In other aspects, the SAP 16 of adjacent fiber-SAP particles 19a and 19b contacts. In some aspects, the fibers 21 of fiber-SAP particles 19a and 19b can keep adjacent fiber-SAP particles 19a and 19b at least partially spaced apart, forming a wicking path 27 between adjacent fiber-SAP particles 19a and 19b. The wicking path 27 can allow fluid flow therebetween, which can improve fluid distribution between the fiber-SAP particles. When incorporated into an absorbent core, the entanglement and / or rigidity of the fibers 21 can promote the fixation of the fiber-SAP particles therein, promoting the formation of such a wicking path.

[0110] Fiber-SAP particle network

[0111] Figure 3A An exemplary network 119 of fiber-SAP particles 19a is depicted. As shown, the network 119 can include one or more fiber-SAP particles (e.g., 19d) having fibers that are entangled with fibers of adjacent fiber-SAP particles, and one or more fiber-SAP particles (e.g., 19c) having fibers that are not entangled with fibers of adjacent fiber-SAP particles.

[0112] Absorbent core

[0113] refer to Figure 7 , the fiber-SAP particles 19 may be deposited on a substrate 2000, such as a nonwoven (e.g., a bulky nonwoven). A cover layer 3000, such as a nonwoven or a bulky nonwoven, may be placed over the substrate 2000 so that the fiber-SAP particles 19 are located between the outer surface 2001 of the substrate 2000 and the outer surface 3001 of the cover layer 3000, and between the inner surface 2003 of the substrate 2000 and the inner surface 3003 of the cover layer 3000, forming an absorbent core 1050.

[0114] Absorbing particles

[0115] The fiber-SAP particles 19 can be incorporated into an absorbent core and / or absorbent article, such as an absorbent core of a diaper. In some aspects, the fiber-SAP particles 19 can be used in combination with a conventional SAP (i.e., a non-fiber-SAP) without fibers 21 thereon. For example, referring to Figure 4 , the absorbent core 1050 of the diaper 1000 may include one or more sections, pockets, regions, strips, lanes, or combinations thereof, region 1019, containing fiber-SAP particles and one or more sections, pockets, regions, strips, lanes, or combinations thereof, regions 1030a and 1030b, containing non-fiber-SAP and free of fiber-SAP particles. The absorbent core 1050 may be incorporated into the body 1051 of the diaper 1000 by any method, including those methods known to those skilled in the art.

[0116] During use of an article containing fiber-SAP particles 19 (eg, a diaper incorporating such fiber-SAP particles), fibers 21 attached to SAP 16 may act as a buffer for the SAP 16 core, resulting in less compression of the SAP 16 core; thereby maintaining the swellability of SAP 16.

[0117] Method for making fiber-SAP and absorbent core and articles comprising the same

[0118] Figure 5A and 5B is a flow chart of a method according to certain aspects of the present disclosure. Figure 1 , 1A , 8A, 8B, 10A and 10B to implement the systems and / or devices depicted Figure 5A and 5B to form one or more particles such as Figure 2 , 2A , Fiber-SAP particles 19 as described in 2B, 3 or 3A, and / or as Figure 4 The diaper 1000 depicted, and / or Figure 7 An absorbent core 1050 is depicted.

[0119] The method may include providing a liquid suspension containing fibers and a solvent (5000). For example, the liquid suspension may be a slurry of MFC, NFC, or a combination thereof in water and / or ethanol.

[0120] The method may include a spray drying stage in which the liquid suspension is spray dried into a fluidized bed chamber (eg, chamber 24 of apparatus 100) (5002).

[0121] In some aspects, the method may include a heating phase in which the liquid suspension is spray dried into a heated environment or region of the fluidized bed chamber (5004). For example, the heating region 31 may be heated to a temperature above the ambient temperature surrounding the device 100, such as above room temperature (i.e., above 20 degrees Celsius).

[0122] The method may include a mixing stage in which SAP, or SAP and additives, are introduced into the fluidized bed chamber and mixed with fibers of the liquid suspension to form fiber-SAP particles, wherein the fibers are adhered and / or bonded to the SAP particles (5006). Figure 1 100, the SAP 16 and the additive 18 may be mixed prior to entering the chamber 24 of the apparatus 100. Furthermore, although the liquid suspension and the additive 18 are introduced separately in Figure 1 100, the liquid suspension and additive 18 may be mixed prior to entering chamber 24 of apparatus 100. During the mixing stage, turbulence and / or heat may be used to mix and initiate interaction between SAP 16, fibers 21 of the liquid suspension, and any additives present to form fiber-SAP particles 19.

[0123] In some aspects, the method includes controlling the flow or input (5008) of the spray-dried fibers 21, SAP 16, and any additives 18 to control the chemical and / or physical properties of the resulting fiber-SAP particles 19.

[0124] In some aspects, the method includes wetting the surface of the SAP in the chamber of the device (5010). The wetting of the surface of the SAP 16 can be accomplished by spray drying the vapor formed by the liquid suspension, by introducing the vapor into the chamber 24 of the device 100, or a combination thereof. As previously described, wetting the surface of the SAP 16 can promote the adhesion and / or bonding of the fibers 21 to the surface of the SAP 16. In some aspects, the surface of the SAP 16 is pre-wetted before being introduced into the chamber 24.

[0125] The method may include forming a channel from the surface of the SAP to the interior of the SAP having the fibers (5012). For example, as described above, the fibers 21 may become at least partially embedded therein during interaction with the SAP 16.

[0126] The method may include a corona treatment stage (5014) in which a corona discharge plasma is used to modify the surface of the SAP, fibers and / or fiber-SAP particles.

[0127] The method may include a crosslinking step (5016) in which the surface of the SAP and / or fiber-SAP particles is at least partially crosslinked. The crosslinking step may be performed before, simultaneously with, or after the corona treatment stage.

[0128] The method may include a collection stage (5018) in which the fiber-SAP particles are collected and an optional additional drying stage in which the fiber-SAP particles are dried.

[0129] In some aspects, the method may include functionalizing the fibers, SAP, fiber-SAP, or a combination thereof in a functionalization stage (5020). Functionalization of fiber 21 and / or SAP 16 may occur within or upstream of the fluidized bed chamber. Functionalization of fiber-SAP 19 may occur within or downstream of the fluidized bed chamber. For example, fiber 21, SAP 16, and / or fiber-SAP 29 may be functionalized with: metal ions for antimicrobial and odor reduction properties; polyelectrolyte complexes that may increase cation exchange capacity; other functional additives, such as for biosensing; clay bentonite particles; and cross-linked particles. In some aspects, the fibers and / or SAP particles are functionalized prior to introduction into the chamber.

[0130] The method may include incorporating fiber-SAP particles into a diaper and / or absorbent core (5022). For example, the fiber-SAP may form part of the absorbent core 1050 of the diaper 1000.

[0131] The method may include forming wicking channels or pathways between adjacent fiber-SAP particles within the absorbent core (5024).For example, the fiber-SAP particles 19 may be deposited such that adjacent fiber-SAP particles 19 are at least partially spaced apart.

[0132] refer to Figure 5A and 5B , one or more of the steps may be eliminated. Moreover, Figure 5A and 5B Additional steps not set forth in the method are also included in the method. In addition, the steps of the method are not limited to Figure 5A and 5B The specific order shown can be Figure 5A and 5B The order not shown occurs.

[0133] Figure 6 is a flow chart of a method according to certain aspects of the present disclosure. Figure 1 , 1A , 8A, 8B, 10A and 10B to implement the systems and / or devices depicted Figure 6 to form one or more particles such as Figure 2 , 2A , Fiber-SAP particles 19 as described in 2B, 3 or 3A, and / or as Figure 4 Diaper 1000 and / or Figure 7 The absorbent core 1050 is shown.

[0134] The method can include providing a liquid suspension containing fibers and a solvent (6000).

[0135] The method may include a spray drying stage (6002) in which the liquid suspension is spray dried into a fluidized bed chamber (e.g., chamber 24 of apparatus 100).

[0136] The method may include a mixing stage (6004) in which SAP or SAP and additives are introduced into the fluidized bed chamber and mixed with the fibers in the liquid suspension to form fiber-SAP particles, wherein the fibers are adhered and / or bonded to the SAP particles.

[0137] The method may include a collecting stage (6006) in which the fiber-SAP particles are collected and an optional additional drying stage in which the fiber-SAP particles are dried.

[0138] The method may include incorporating the fiber-SAP particles into a diaper and / or an absorbent core (6008).

[0139] refer to Figure 6 , one or more of the steps may be eliminated. Moreover, Figure 6 Additional steps not set forth in the method are also included in the method. In addition, the steps of the method are not limited to Figure 6 The specific order shown can be Figure 6 The order not shown occurs.

[0140] Fig. 6A is a flow chart of a method according to certain aspects of the present disclosure. Figure 1 , 1A , 8A, 8B, 10A and 10B to implement the systems and / or devices depicted Fig. 6A to form one or more particles such as Figure 2 , 2A , Fiber-SAP particles 19 as described in 2B, 3 or 3A, and / or as Figure 4 The diaper 1000 depicted and / or Figure 7 The absorbent core 1050 is shown.

[0141] The method may comprise at least partially drying the fibers of the liquid suspension of fibers and solvent. The partial drying may be performed by atomization of the liquid suspension.

[0142] The method may include a mixing stage in which the SAP is mixed with at least partially predried fibers of a liquid suspension to form fiber-SAP particles. In some aspects, the SAP is pre-wetted prior to mixing, such as by deposition of moisture dried from the fibers. Fig. 6A The method can be compared with the reference Figure 5A , 5B , 6 and 9 shown and described any one or more of the steps combined.

[0143] Electrostatic charging

[0144] In some aspects, the fiber-SAP particles 19 are electrostatically charged. This electrostatic charging can be performed in the chamber 24, in the collection area 26, or downstream of both the chamber 24 and the collection area 26. The electrostatic charge causes the free ends of the fibers to rise and extend outward from the outer surface 25 of the SAP 16 core particle. Thus, the electrostatic charging can increase the "fluffiness" of the fiber-SAP particles 19 by "lifting" the free ends of the fibers off the SAP 16 surface to extend outward therefrom.

[0145] Relative size of fibers and SAP

[0146] In some aspects, the relative sizes of SAP core particles 16 and fibers 21 are selected to eliminate or at least minimize the occurrence of entanglement of fibers 21 around SAP 16 .

[0147] Opening and closing of cracks

[0148] refer to Figure 2A and 2B , a fiber-SAP particle 19e is shown before and after drying. When the SAP core particle is wetted, the SAP swells. Any cracks present on the outer surface 25 of the SAP particle will expand when the SAP swells. Figure 2A The cracks 230a are shown in a swollen state. This opening or expansion of the cracks 230a allows fibers, such as fiber 21c, to fit more easily into the cracks 230a. Such embedding of the fibers 21c into the cracks 230a can occur, for example, within the mixing region 33. Upon subsequent drying of the fiber-SAP particles 19e (drying 231), the fiber-SAP particles 19e shrink and the cracks on the outer surface 25 shrink accordingly. Thus, as shown in FIG. Figure 2B As shown, when the fiber-SAP particle 19 is in a swollen state, the crack 230b is relatively closed compared to the same crack. By promoting further interactions between the fiber 21c and the core SAP particle (e.g., H-bonding, polymer entanglement, etc.), the closure of the SAP crack around the fiber can stabilize the attachment of the fiber 21c to the core SAP particle, thereby strengthening the bond therebetween. In some aspects, the relative closure of the crack around the fiber traps the fiber therein. In some aspects, a fiber having a diameter corresponding to the width of the crack in the SAP outer surface 25 is selected so that the diameter of the fiber can fit within the crack at least when the crack is in a swollen state.

[0149] Figure 2Cis a SEM of a SAP (solution polymerized) with an irregular surface, including wrinkles and cracks on its surface. Figure 2D is a SEM of a light and heat cross-linked SAP in a dry, fully swollen, and re-dried state. In some aspects of the disclosure, the SAP does not become fully swollen, but rather partially swollen.

[0150] Process / system area

[0151] refer to Fig. 8A , certain aspects of the processes, systems, and devices described herein are discussed. System 800 includes multiple regions within which different steps of the process can be performed. A first region 801 is an introduction region in which a liquid suspension is provided. Within the first region 801, the liquid suspension is atomized to form an aerosol thereof. In some aspects, the first region 801 is free of SAP.

[0152] The second region 802 is a pre-drying region, in which at least some of the liquid of the liquid suspension flashes from the fiber and enters the surrounding environment. The partial drying of the fiber can allow the fiber to move more dynamically in the system 800, because the fiber is lighter in a dry state. In some aspects, before the fiber contacts the SAP, the liquid flashed out from the fiber flows into contact with the SAP. When the liquid flashes into steam, the steam diffuses in the whole system 800, and due to the turbulent airflow pattern in the system 800, the fiber remains in a relatively suspended state in the air in the system 800. The steam can be deposited on the SAP, resulting in the pre-wetting of the SAP. This pre-wetting of the SAP results in at least partial swelling of the SAP, making the SAP easily attached to the fiber (e.g., making the fiber embed therein). In some aspects, the second region 802 does not have SAP.

[0153] The third zone 803 is a SAP introduction zone. Although the SAP introduction zone 803 is shown downstream (ie, after) the liquid suspension introduction zone 801 and the pre-drying zone 802, the system 800 is not limited to this particular arrangement.

[0154] The fourth region 804 is a mixing region, in which SAP, fiber, steam and air are turbulently mixed together. In the mixing region 804, each of SAP, fiber, steam and air remains suspended under turbulent conditions to promote mixing and interaction between them. Although shown as separated, the fourth region 804 can overlap with the third region 803. In some aspects, the stirring in the mixing region is enough to separate the fiber interacting with the unswollen SAP from the unswollen SAP, and can then be attached to the swollen SAP.

[0155] The fifth zone 805 is an optional reaction zone in which one or more chemical reactions or other modification methods may be used to modify the SAP, fibers, fiber-SAP particles, or a combination thereof. Although shown as downstream of the mixing zone 804, the reaction zone may coincide with the mixing zone or be upstream thereof. In some aspects, the reaction zone 805 is a corona treatment zone and / or an electrostatic charging zone.

[0156] The sixth zone 806 is a drying zone. In the drying zone 806, the fibers, SAP, fiber-SAP particles, or a combination thereof are dried, for example, by heat, air flow, residence time, or a combination thereof. Although shown as downstream of the mixing zone 804 and the optional reaction zone 805, the drying zone may coincide with the mixing zone 804 and / or the optional reaction zone 805 or be upstream of the mixing zone 804 and / or the optional reaction zone 805.

[0157] The seventh zone 807 is a collection zone where fiber-SAP particles are collected, optionally in combination with fibers and / or SAP. Although shown downstream of the drying zone 806, the collection zone may coincide with the drying zone.

[0158] refer to Figure 8B , discusses certain aspects of the processes, systems, and apparatus described herein. System 800b includes multiple areas in which different steps of the process can be performed.

[0159] Region 810 is a pre-drying region, in which at least some liquids of a liquid suspension flash from the fiber and enter the surrounding environment. The partial drying of the fiber can allow the fiber to move more dynamically in system 800b, because the fiber is lighter in a dry state. In some aspects, before the fiber contacts SAP, the liquid flashed out from the fiber flows into contact with the SAP. When the liquid flashes into steam, the steam diffuses in the entire system 800b, and due to the turbulent airflow pattern in the system 800b, the fiber keeps a relative suspension state in the air in the system 800b. The steam can be deposited on the SAP, resulting in the pre-wetting of the SAP. This pre-wetting of the SAP results in at least a partial swelling of the SAP, making the SAP easily attached to the fiber (e.g., making the fiber embed therein). In some aspects, region 810 does not have SAP.

[0160] Region 812 is a mixing region, in which SAP, fiber, steam and air are turbulently mixed together. In mixing region 812, each of SAP, fiber, steam and air remains suspended under turbulent conditions to promote mixing and interaction between them.

[0161] Fig. 8A Any one or more of the regions shown and described in may be used within system 800b.

[0162] Although each area Fig. 8A and 8B As separate and distinct regions, in some aspects, one or more regions overlap with each other. Moreover, although each region is shown as Fig. 8A and 8B As shown, as being within a single system, in some aspects one or more regions are located in a separate system from other regions.

[0163] In some respects, the residence time in each zone is controlled. In some respects, one or more zones can be selectively isolated from adjacent zones of the system so that the fluid between the selectively controlled zones is communicated. Some mechanisms for controlling the residence time and the input rate of ingredients include using intermittent spray drying (or other liquid suspension introduction methods), controlling the size of the zone and / or chamber, controlling the airflow relative to the system, and positioning one or more zones in a separate chamber.

[0164] Fig. 9 Depicted is a schematic diagram of a method according to certain aspects of the present disclosure. Fig. 9 As shown, a fiber liquid suspension is supplied (step 1900). The fiber liquid suspension undergoes a premix drying stage (step 1902). In step 1902, the fibers of the fiber liquid suspension are at least partially dried by forming an aerosol of the liquid suspension, dispersing the liquid and fibers in air or another gaseous medium.

[0165] Optionally, at least some of the liquid dispersed and / or dried from the fibers in step 1092 can be directed to contact the SAP (step 1903). SAP is supplied by a SAP supply source (step 1904), optionally to a SAP pre-swelling region, for pre-wetting of the SAP in step 1905. This pre-wetting of the SAP activates the SAP surface for attachment to the fibers by swelling and softening the SAP.

[0166] In step 1906, the pre-wetted SAP (or optional dry SAP) is mixed with the partially dried fibers from step 1902. The mixing of the SAP with the fibers results in attachment of the fibers to the SAP, forming fiber-SAP particles.

[0167] Optionally, in step 1908, the fiber-SAP particles are further dried.

[0168] Optionally, in step 1910, the fiber-SAP particles are collected.

[0169] Optionally, additives are introduced at step 1911 .

[0170] refer to Figure 5A , 5BAny one or more of the steps described in 6 and 6A may be combined with reference Fig. 9 Combination of the steps described.

[0171] Fig. 10A depicts a schematic diagram of an apparatus for attaching fibers to SAP according to certain embodiments, and Fig. 10B Describe its cross-sectional view along line AA. Chamber 24 may include expansion section 24b, which has a larger cross-sectional area than the upper part of chamber 24a. Fiber liquid suspension is introduced into the chamber upstream of expansion portion 24b and flows downward into expansion section 24d. When entering expansion section 24b, fiber has been at least partially dried, as described elsewhere herein. Therefore, fiber 21 and steam 12b flow into expansion section. SAP 16 is introduced into expansion section 24b outside the central flow channel 1021 of chamber 24. Although fiber 21 is guided to flow at least substantially along the central flow channel 1021 of chamber 24 by gravity, steam 12b is less affected by gravity and flows freely through chamber 24 (e.g., fluid flow path 1023) included in expansion section 24b as a fluid. Thus, SAP 16 and steam 12b are mixed in expansion section 24b before SAP 16 is mixed with fibers 21 or at least before SAP 16 is substantially mixed with fibers 21 within central flow channel 1021. Thus, pre-wetted, partially swollen SAP 16b can contact fibers 21 within central flow channel 1021 to form fiber-SAP particles 19, which are directed out of chamber 24 via outlet 24c and optionally into additional drying and / or collection regions 1026.

[0172] like Fig. 10B As shown, along the periphery of the expansion section 24b, the SAP swells, and as the SAP circulates and flows within the expansion section 24b and moves closer to the central flow channel, the SAP 16 becomes increasingly swollen by contact with the steam and its deposition. Therefore, when the SAP reaches the central flow channel and contacts the fibers, the SAP is pre-wetted and pre-swollen (and thus activated to contact and adhere to the fibers) to form fiber-SAP particles 19.

[0173] Those skilled in the art will appreciate that other arrangements and configurations may be used to provide pre-wetting of the SAP, evaporating the liquid from the fibers prior to contact between the SAP and the fibers. Furthermore, those skilled in the art will appreciate that Fig. 10A and 10B The schematic diagrams are not to scale and are for illustration purposes only.

[0174] refer to Fig.11, in another aspect of the present disclosure, a schematic diagram of an exemplary system 1101, apparatus 1101, and process / method 1101 is shown for forming fiber-attached (preferably embedded) SAP particles. The system or apparatus 1101 includes a mixing area or chamber 1103, wherein particles of SAP 1131, desired additives 1133, and partially spray-dried fibers 1134 (with liquid thereon) are presented together for mixing. The fibers are introduced by a spray drying device 1105, directing the fiber-liquid suspension into the apparatus 1101. The mixing area 1103 typically holds fiber-SAP particles of varying dryness. These particles are suspended in the mixing area 1103 and sometimes circulated and then passed through.

[0175] This simplified diagram depicts two outlets or collection points 1122 for fiber-attached (preferably embedded) SAP particles. In this example, fluidizing air jets 1111 are used with (or without) heating elements to transfer heat to the mixed dynamics (in the preferred mixing zone 1103) and promote further drying. The air jets 1111 can be adjusted (controlled) to present the desired buoyancy in the mixing zone (to suspend the fiber-SAP mixture) and also create turbulent eddies. Depending on whether the desired finished particles (dried) are heavier or lighter than the buoyancy generated by the air jets 1111, an outlet 1122 is determined, through which the finished fiber-SAP particles can be collected or transferred to the next layer (e.g., a treatment layer such as corona treatment or cross-linking or collection).

[0176] In further variations using fluidized bed technology, the fiber-SAP mixture can be circulated to generate centrifugal forces that help separate particles between two (or more) degrees of dryness. In certain variations, the dry particles are separated and / or separated and discharged from the mixing chamber, while other or remaining particles undergo further residence time, circulation and / or drying and / or are recycled in the system to form fiber-SAP particles. In one application, a cyclone device can be used to act on the fiber-SAP particles, which can then be separated by angular velocity. In any case, one aspect and advantageous feature of the apparatus, system and method can identify or separate the target final product by identifying and manipulating the balance of forces between buoyancy, drag, weight and others (such as centrifugal force). In a specific example, attention is focused on the difference in basic properties (such as weight and surface area) between the starting and finished fiber-SAP particle products to facilitate the collection and separation of the finished product.

[0177] The foregoing description has been presented for the purpose of illustration and description. It should be noted that the description is not intended to limit the embodiments to the various articles, products, systems, devices and processes disclosed herein. The various aspects of the embodiments as described above may be applicable to other types of disposable absorbent articles and clothing and methods of making the same. For example, the absorbent composite and its method of making the same as described above may be incorporated into other products and methods of making the same. In addition, the processes described herein may be used to produce compositions, clothing and articles other than those described herein. For technicians associated with the consumer products provided by the present disclosure, these variations of the embodiments will become apparent. Therefore, variations and modifications corresponding to the above teachings and the technology and knowledge of the relevant fields are within the scope of the present disclosure. The embodiments described and shown here are also intended to explain the best mode for practicing the embodiments, and to enable other technicians in the field to utilize the embodiments with various modifications required for the specific application or use of the present embodiments. In addition, the claims attached to this description are provided to clarify or elaborate some different aspects of the methods and products (compositions). These claims are intended to form and describe additional aspects and features of the present disclosure, and are important to the present disclosure.

Claims

1. An absorbent composite comprising: substrate; Covering layer; and a plurality of fiber-SAP particles between the substrate and the cover layer, wherein each fiber-SAP particle comprises a superabsorbent particle and a plurality of fibers attached to and embedded in the superabsorbent particle, and wherein the fibers extend outwardly from an outer surface of the superabsorbent particle; and wherein adjacent fiber-SAP particles in the plurality of fiber-SAP particles are spaced apart such that a wicking path is provided between adjacent spaced apart fiber-SAP particles; The fiber-SAP particles are manufactured by the following method, which comprises: providing the plurality of fibers as wetted fibers; dispersing the wetted fibers in a gaseous medium such that the wetted fibers are suspended in the gaseous medium; and The wetted fibers suspended in the gaseous medium are mixed with superabsorbent particles (SAP) such that at least some of the fibers become attached to the SAP, thereby forming fiber-SAP particles.

2. The absorbent composite of claim 1, wherein the channels along the fibers increase the absorption rate of the superabsorbent particles.

3. The absorbent composite of claim 1, wherein the fibers embedded in the superabsorbent particles penetrate a distance through the outer surface of the superabsorbent particles and into the interior of the superabsorbent particles.

4. The absorbent composite of claim 1, wherein providing the wetted fibers comprises providing the fibers in a liquid suspension and forming an aerosol of the liquid suspension, the liquid suspension comprising the wetted fibers; and Wherein mixing the wetted fibers with SAP comprises mixing an aerosol of the liquid suspension with superabsorbent particles (SAP).

5. The absorbent composite of claim 1 , wherein dispersing the wetted fibers in a gaseous medium comprises forming an aerosol, the aerosol comprising the wetted fibers suspended in a gaseous medium; and Wherein mixing the wetted fibers with SAP comprises mixing the aerosol with superabsorbent particles (SAP).

6. The absorbent composite of claim 1, wherein a method of making the fiber-SAP particles comprises: Wetting the SAP so that cracks in the SAP are at least partially opened; mixing the plurality of fibers with wetted SAP such that at least some of the fibers are embedded in crevices of the SAP; and The SAP is dried so that the cracks having the fibers embedded therein are at least partially closed, thereby forming fiber-SAP particles.

7. The absorbent composite of claim 6, wherein the method of making the fiber-SAP particles comprises: After drying the SAP, the SAP is crosslinked to the fibers, the fibers are crosslinked to other fibers of the fibers, the SAP is crosslinked, or a combination thereof.

8. The absorbent composite of claim 1, wherein at least some of the fibers are covalently bonded to SAP.

9. The absorbent composite of claim 1, wherein: The fibers of adjacent fiber-SAP particles are entangled with each other.

10. The absorbent composite of claim 1, wherein the substrate is a nonwoven, wherein the cover layer is a nonwoven, or a combination thereof.

11. The absorbent composite of claim 1, wherein: At least some of the fibers have a first end attached to the superabsorbent particle and a second end free to move relative to the superabsorbent particle.

12. The absorbent composite of claim 1, wherein: Each superabsorbent particle includes fibers adhered thereto, fibers hydrogen bonded thereto, fibers entangled with the polymer chains of the superabsorbent particle, or a combination thereof.

13. The absorbent composite of claim 1, wherein: At least some of the superabsorbent particles include fibers extending from the superabsorbent particles, perpendicular to an outer surface of the superabsorbent particles.

14. The absorbent composite of claim 1, wherein: The plurality of fibers include fibers cross-linked with superabsorbent particles, fibers cross-linked with other fibers of the plurality of fibers, or combinations thereof.

15. The absorbent composite of claim 1, wherein: The fibers embedded in the superabsorbent particles form channels into the interior of the superabsorbent particles.

16. The absorbent composite of claim 1, wherein: The outer surfaces of the superabsorbent particles are at least partially crosslinked.

17. The absorbent composite of claim 1, wherein: The fibers include textile fibers.

18. The absorbent composite of claim 1, wherein: The fibers include microfibrillated cellulose fibers.

19. The absorbent composite of claim 1, wherein the fibers comprise hydrophilic fibers.

20. The absorbent composite of claim 1, wherein the fibers comprise nanofibrillated cellulose fibers.

21. The absorbent composite of claim 1, wherein the fibers, the superabsorbent particles, or a combination thereof are functionalized.

22. The absorbent composite of claim 1, wherein: The superabsorbent particles include fibers embedded within crevices of the superabsorbent particles.

23. The absorbent composite of claim 22, wherein the slits are closed around the embedded fibers.

24. The absorbent composite of claim 23, wherein the cracks stabilize the attachment of the fibers to the superabsorbent particles.

25. The absorbent composite of claim 24, wherein the crevices entrap the fibers.

26. An absorbent article comprising: main body; and an absorbent core composite supported on the body, the absorbent core composite comprising a substrate, a cover layer, and a plurality of fiber-SAP particles located between the substrate and the cover layer, wherein each fiber-SAP particle comprises a superabsorbent particle and a plurality of fibers attached to and embedded in the superabsorbent particle, wherein the fibers extend outwardly from an outer surface of the superabsorbent particle; and wherein adjacent fiber-SAP particles in the plurality of fiber-SAP particles are spaced apart such that a wicking path is provided between adjacent spaced apart fiber-SAP particles; The fiber-SAP particles are manufactured by the following method, which comprises: providing the plurality of fibers as wetted fibers; dispersing the wetted fibers in a gaseous medium such that the wetted fibers are suspended in the gaseous medium; and The wetted fibers suspended in the gaseous medium are mixed with superabsorbent particles (SAP) such that at least some of the fibers become attached to the SAP, thereby forming fiber-SAP particles.

27. The absorbent article according to claim 26, wherein fibers of adjacent fiber-SAP particles are entangled with each other.

28. The absorbent article of claim 26, wherein the substrate is a nonwoven, wherein the cover layer is a nonwoven, or a combination thereof.

29. The absorbent article according to claim 26, wherein: At least some of the fibers have a first end attached to the superabsorbent particle and a second end free to move relative to the superabsorbent particle.

30. The absorbent article of claim 26, wherein: Each superabsorbent particle includes fibers adhered thereto, fibers hydrogen bonded thereto, fibers entangled with the polymer chains of the superabsorbent particle, or a combination thereof.

31. The absorbent article of claim 26, wherein: At least some of the superabsorbent particles include fibers extending from the superabsorbent particles, perpendicular to an outer surface of the superabsorbent particles.

32. The absorbent article of claim 26, wherein: The plurality of fibers include fibers cross-linked with superabsorbent particles, fibers cross-linked with other fibers of the plurality of fibers, or combinations thereof.

33. The absorbent article of claim 26, wherein: The fibers embedded in the superabsorbent particles form channels into the interior of the superabsorbent particles.

34. The absorbent article of claim 26, wherein: The outer surfaces of the superabsorbent particles are at least partially crosslinked.

35. The absorbent article of claim 26, wherein: The fibers include textile fibers.

36. The absorbent article of claim 26, wherein: The fibers include microfibrillated cellulose fibers.

37. The absorbent article of claim 26, wherein the fibers comprise hydrophilic fibers.

38. The absorbent article of claim 26, wherein the fibers comprise nanofibrillated cellulose fibers.

39. The absorbent article of claim 26, wherein the fibers, the superabsorbent particles, or a combination thereof are functionalized.

40. The absorbent article of claim 26, wherein: The superabsorbent particles include fibers embedded within crevices of the superabsorbent particles.

41. A system for forming fiber-SAP particles, comprising: a chamber containing a gaseous medium, the chamber comprising a first inlet and a second inlet; a supply of a fiber-liquid suspension in fluid communication with the first inlet, wherein the fiber-liquid suspension comprises fibers suspended in a liquid, and wherein the first inlet comprises a first nozzle positioned to disperse the fiber-liquid suspension into the gaseous medium within a first region of the chamber; and A supplier of superabsorbent particles in fluid communication with the second inlet, wherein the second inlet includes a second nozzle positioned to disperse the superabsorbent particles into a second region of the chamber, wherein the second region is downstream of and in fluid communication with the first region.

42. The system of claim 41, wherein the second inlet is located downstream of the first inlet.

43. The system of claim 41, wherein the first nozzle comprises an atomizer.

44. The system of claim 41 further comprising a corona treatment zone at least partially coincident with or downstream of the second zone.

45. The system of claim 41 further comprising a collection zone downstream of the second zone, the collection zone positioned to collect the fiber-SAP particles.

46. ​​The system of claim 41, wherein the chamber is a fluidized bed chamber.

47. The system of claim 41 further comprising a third inlet positioned to introduce an additive into the chamber.

48. The system of claim 43, wherein the nebulizer comprises an ultrasound-assisted spray device.

49. The system of claim 41, wherein the first region and the second region are vertically aligned, and the first region is in fluid communication with the second region.

50. The system of claim 41, wherein the first nozzle is positioned to disperse the fiber-liquid suspension into the chamber in a first direction, wherein the second nozzle is positioned to disperse the superabsorbent particles into the chamber in a second direction, and wherein the second direction is at an angle relative to the first direction.

51. The system of claim 50, wherein the angle is between 15 and 180 degrees.

52. The system of claim 45, wherein the collection area comprises a conduit, a circulating jet in fluid communication with the conduit, a heating element, and a pump positioned to pump the fiber-SAP particles from the conduit.

53. The system of claim 41, wherein the chamber comprises an upper portion where the first inlet is located, a lower portion, and a middle portion where the second inlet is located, wherein: The middle portion has a larger cross-sectional area than the upper portion.

54. The system of claim 41, wherein the chamber includes fluidizing air jets positioned to provide turbulence within the chamber.

55. The system of claim 41, wherein the chamber includes a heating element positioned to heat the chamber.

56. An absorbent composite comprising: substrate; Covering layer; a plurality of fiber-SAP particles between the substrate and the cover layer, wherein each fiber-SAP particle comprises a superabsorbent particle and a plurality of fibers attached to and embedded in the superabsorbent particle, wherein the fibers extend outwardly from an outer surface of the superabsorbent particle, and wherein the plurality of fibers comprises fibers cross-linked to the superabsorbent particle, fibers cross-linked to other fibers of the plurality of fibers, or a combination thereof; wherein adjacent fiber-SAP particles in the plurality of fiber-SAP particles are spaced apart such that a wicking path is provided between adjacent spaced apart fiber-SAP particles; The fiber-SAP particles are manufactured by the following method, which comprises: providing the plurality of fibers as wetted fibers; dispersing the wetted fibers in a gaseous medium such that the wetted fibers are suspended in the gaseous medium; and The wetted fibers suspended in the gaseous medium are mixed with superabsorbent particles (SAP) such that at least some of the fibers become attached to the SAP, thereby forming fiber-SAP particles.

57. An absorbent composite comprising: substrate; Covering layer; and A plurality of fiber-SAP particles located between the substrate and the cover layer, wherein each fiber-SAP particle comprises: superabsorbent particles; and a plurality of fibers attached to and embedded in the superabsorbent particle, wherein the fibers extend outwardly from an outer surface of the superabsorbent particle, and wherein the fibers include fibers cross-linked to the superabsorbent particle and fibers cross-linked to other fibers of the plurality of fibers; wherein adjacent fiber-SAP particles in the plurality of fiber-SAP particles are spaced apart such that a wicking path is provided between adjacent spaced apart fiber-SAP particles; The fiber-SAP particles are manufactured by the following method, which comprises: providing the plurality of fibers as wetted fibers; dispersing the wetted fibers in a gaseous medium such that the wetted fibers are suspended in the gaseous medium; and The wetted fibers suspended in the gaseous medium are mixed with superabsorbent particles (SAP) such that at least some of the fibers become attached to the SAP, thereby forming fiber-SAP particles.

58. An absorbent composite comprising: substrate; Covering layer; and A plurality of fiber-SAP particles located between the substrate and the cover layer, wherein each fiber-SAP particle comprises: superabsorbent particles; and a plurality of fibers embedded in the superabsorbent particles, wherein the fibers extend outwardly from an outer surface of the superabsorbent particles, wherein the fiber-SAP particles are made by a process comprising: spray drying a liquid suspension of the fibers into a chamber; introducing the superabsorbent particles into the chamber; colliding the fibers with the superabsorbent particles in an aerosol medium in the chamber, and turbulently mixing the fibers with the superabsorbent particles in the chamber such that the fibers are embedded in cracks of the superabsorbent particles; and drying the fibers and the superabsorbent particles such that the cracks close around the embedded fibers; Wherein adjacent fiber-SAP particles in the plurality of fiber-SAP particles are spaced apart such that a wicking path is provided between adjacent spaced apart fiber-SAP particles.

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